Draft gear



E. H. SCHMIDT DRAFT GEAR Filed Nov. 11, 1930 2 Sheets-Sheet 1 E. H. SCHMIDT.

Dec. 5, 1933.

DRAFT GEAR 2 Sheets-Sheet 2 .I/I/l/ Filed Nov. 11, 1930 O J MEM wY cw ww ww wm l. wm

Patented Dec. 5, 1933- DRAFT GEAR Ernest H. Schmidt, ClevelandHeights, Ohio as'-- signor to National Malleable and SteelCast ings Company, Cleveland, Ohio, a corporation of Ohio Application November 11', 193Gv Serial No. 494,886

14. Claims.

This invention has for an object the provision of a novel and improved railway draft gear. Among the features of the invention is the provision of a friction draft gear, simple in construction, effective in operation, and capable of being readily substituted for the standard Farlow twin spring draft gear. Other features of the invention will be hereinafter described.

In the accompanying drawings:

Fig. 1 is a view partly in plan and partly in horizontal section taken on line 11 of Fig. 2 and showing a draft gear embodying my invention, together with associated connections, in assembled relation on a car;

Fig. 2 is a view partly in side elevation and partly in vertical section taken on line 2-2 of Fig. 1.

Fig. 3 is a horizontal sectional view of the draft gear on line 3.-3 of Fig. 4. n

Fig. 4 is a vertical longitudinal sectional view of the draft gear, and

Figs. 5 and 6 are transverse vertical sectional views taken on lines 55 and 6-6 respectively of Fig. 4.

Fig. 7 is 'a detail view of a spring employed in the gear.

Referring to the drawings, draft sills 55 of standard construction are shown, said draft sills being positioned under the floor of a car, as is well understood. Said sills are slotted for the reception of draft keys 6, I, and 8, respectively. The key 6 extends through slots 9, 9 in the respective sills, and also through a slot 10 in a coupler shank 11 of standard construction. The key '7 extends through slots 12, 12 in the respective sills, while key 8 projects through slots 13, 13 in said sills. The keys, 6,v 7, and 8 also extend through slots in arms or links 14,714. The arrangement thus far described is that of the standard Farlow draft rigging.

In carrying out my invention I provide a member 15 comprising a portion 15 having a slot 16 for receiving the key 8 and also comprising a casing portion 15" shown as rectangular in form, in opposite sides of which are seated friction members 17, 17. Each of said friction members preferably consists of a block having at its inner end a lateral projection 18 which engages a recess 19in the adjacent side of the casing 15". The inward thrust of the members 17, 1'7 is received by the wall 20 of the member 15, which wall separates the casing portion 15" from the portion 15 or said member. Ribs 21 extending from wall20 to the rear end of member 15 serve to brace said wall.

follower On opposite sides-0f each of the friction members 17, 17, and in frictional engagement therewith are arranged friction shoes 22, two friction members and four shoes being provided. The inclined forward faces of the shoes 22 are engaged by correspondingly inclined faces 23 or a wedge member 24. u

The wedge member 24 is provided with a slot 25 for receiving the draft key 7. A spring 26, arranged ccaxially with the longitudinal axis of the casing 15" bears at one end against the central portion of wall 20 and at its other end against the central portion of the inner face of said wedge member. Projections 27, 28 on said wall and wedge member, respectively, extend into the opposite endsof said spring 26 and serve to center the latter.

Surrounding the spring 26 are outer and inner spring coils 29, 30, respectively, each of which bears at one end against the wall 20 and at the other against a spring follower 31. 'The latter is provided with four extensions 32, each of which engages a corresponding one of the friction shoes 22. The follower 31 is also provided with flanges 83 curved at their inner edges 33 as shown for 30 receiving the spring 29 and centering the latter. The extensions 32 are shown merging with said flanges. Reinforcing ribs 34 also merge with the projections 32 and associated flanges 33., The follower 31 has an opening 35 through which the 35 spring 26 extends into engagement with wedge member 24.

l The member 15 and wedge 24 are maintained in assembled relation to each other by means of a pair of bolts 36, 36; each of which projects through an opening in a corresponding one of a pair of lugs 3'7, 37 of wedge 24 and through an opening in the associated one of a pair of lugs 38, 38 of the casing member 15.

, Asshown in Figs. land 2, the members 15 and 24 are positionedbetween the links 14, 14, with the key 7 extending through slot 25 in member 24 and the key 8 passing through slot 16 in member 15. When the parts are in normal position, as shown in Figs. land 2, the member 15 abuts against a stop 39 secured between the draft sills and at the same time the key 7 is in engagement with the front walls of the respective slots 12, 12in said sills. In pull, the coupler, through key 6, moves links 14 forwardly, and thereby, through key 8, moves member 15 forwardly with respect towedge 24. The latter at this time is held from moving forwardly by the engagement of key 7 in the draft sill slots 12, 12 aforesaid. In buff, the coupler, the shank of which abuts the wedge member 24, moves the latter rearwardly with respect to the member 15, which is prevented from moving rearwardly by stop 39 and key 8. It will be apparent that compression of the draft gear in either buff or pull produces relative movement between the pairs of shoes 22 and the associated friction members 1? and that compression of said gear is resisted both by the springs 26, 29, and 30 and by the friction generated between said shoes and friction members. Said shoes, under the influence of the wedge surfaces 23 and springs 29, 30, are maintained in firm frictional engagement with said friction members during the compression of the gear. I have shown the faces of the friction members inclined or tapered, so that said members are thicker at the rear than at the front. Such taper of the friction members increases the friction developed during compression of the gear. The amount of taper may, of course, be varied as desired, or the members 1''! may be made of uniform thickness throughout so that their friction faces are parallel to the longitudinal axis of the gear. The parts of the gear are so proportioned that just before the springs go solid the wedge member 24 will engage the end of the case 15 and thereby protect the springs against oversolid blows. I

While I have shown the projections 18 of the friction members in firm engagement with the openings 19, a limited amount of clearance may be provided between said openings and projections. In this way the initial compression of the gear may be opposed simply by the springs 26, 29, and 30, and further compression thereof both by said springs and by the friction developed between the shoes and friction members. The

extent of preliminary spring action may be variedby varying the amount of said" clearance, and the capacity of the springs.

The draft gear above described may readily be substituted for the standard Farlow twin spring draft gear by merely removing the members of said twin spring gear from the position which they occupy between the end of the coupler shank and the rear stop and then inserting the wedge member 24 and casing member 15 as a unit into the space from which the twin spring gear has been removed. My invention provides not only a simple and highly effective friction draft gear but also one which can be used to replace the standard Farlow twin spring gear without any change in dimensions of the standard space occupied by the latter.

The terms and expressions which I have employed are used as terms of description and not of limitation, and I have no intention, in the use such terms and expressions, of excluding any equivalents of the features shown and described or portions thereof, but recognize that various modifications are possible within the scope of the invention claimed.

I claim:

1. In a draft gear, a case, friction members within the case, a plurality of pairs of friction shoes, each of said pairs being in frictional engagement with a corresponding one of said members, a spring follower having a main portion for engaging a spring and outwardly extending pairs of projections for engaging the shoes, each of said pairs extending on opposite sides of a corresponding friction member, a spring engaging said follower and arranged to be compressed by said shoes, and a wedge engaging said shoes.

within the case, a plurality of pairs of friction shoes, each of said pairs being in friction engagement with a corresponding one of said members, follower means cooperating with each of said shoes, a spring engaging said follower means and arranged to be compressed by said shoes, a wedge exterior to said case and having internal wedging surfaces engaging said shoes, and a spring surrounded by the first mentioned spring and engaging said wedge.

3. In a draft gear, a case, friction members within the case, a plurality of pairs of friction shoes, each of said pairs being in frictional engage'ment with and on opposite sides of a corresponding one of said members, a follower engaging said shoes, a wedge engaging said shoes and so constructed and arranged as to apply wedging pressure simultaneously in opposite directions to the respective shoes of each pair, a spring engaging said follower and arranged to be compressed by said shoes, and a spring surrounded by the first mentioned spring and extending through an opening in said follower into engagement with said wedge.

s. In a draft gear, a case, friction members within the case, a plurality of pairs of friction shoes, each of said pairs being in frictional engagement with and on opposite sides of a corresponding one of said members, a follower provided with projections engaging the respective shoes, said follower also having a central opening therein, a wedge engaging said shoes and so constructed and ar nged as to apply wcdging pres sure simultaneously in opposite directions to the respective shoes of each pair, a spring engaging said follower and arranged to be compressed by said shoes, said follower having means for the centering of said spring, and a spring surrounded by the first mentioned spring and extending through said opening in said follower intoengagement with said wedge.

5. In a draft gear, a casing member having a slot for the reception of a draft key, friction members within said case, a plurality of pairs of friction shoes, each of said pairs being in frictional engagement with a corresponding one of said friction members, spring means arranged to be compressed by said shoes, a wedge member outside said casing and engaging said shoes, said Wedge member having a slot for the reception of a key, and keys in said slots for supporting said draft gear.

6. In a draft gear, a case, friction members within the case, a plurality of pairs of friction shoes, each pair in frictional engagement with a corresponding one of said friction members, spring means arranged to resist movement of said friction shoes, a wedge outside said case and engaging said shoes, said wedge and case being each provided with means for receiving a draft key.

7. In a draft gear, a case, friction members within the case, a plurality of pairs of friction shoes, each pair being in frictional engagement with a corresponding one of said members, a. wedge outside said case and engaging said shoes, a follower engaging said shoes, and a plurality of co-axial springs, arranged to resist compression, one of which engages said follower and the other of which engages said wedge, said case and wedge having slots formed therein for receiving keys to position the gear.

, 8. In a draft gear, a case, friction members within the case, a plurality of pairs of friction shoes, each of said pairs being in frictional engagement with a corresponding one of said members, a spring common to all of said shoes and arranged to be compressed thereby, and a wedge engaging said shoes, said wedge having pairs of wedging surfaces for cooperation with the respective pairs of shoes, the surfaces of each pair beingarranged to apply pressure simultaneously in opposite directions to the corresponding pair of shoes, said wedge and case being provided with key slots and keys in said slots for supporting said draft gear.

9. In a draft gear, a pair of oppositely disposed members, each provided with akeyreceivingopening, one of said members having walls extending therefrom toward the other, separate friction ele-' ments having portions extending into said walls, said elements projecting toward each other into the space between said walls, shoes engaging said friction elements and held apart by the latter, a spring interposed between an end wall of one of said members and said shoes and being compressed by movement of the shoes toward said end wall, one of said members having wedging surfaces engaging the shoes to force them into closer engagement with the friction elements.

10. In a draft gear, a casing rectangular in cross section, a helical spring in said casing,

friction shoes, one in each corner of said casing, arranged about said spring, friction members located within the casing and exteriorly of said spring, one of said friction members being positioned between a pair of said friction shoes for engagement thereby, and the other friction memher being positioned between the other pair of said shoes for engagement thereby, said friction members being mountedin oppositewalls of'said casing, follower means interposed between said spring and said shoes, and a wedge outside said casing and provided with wedging surfaces for engaging said shoes, said wedge and said casing each having a slot for the reception of a draft key. I i

11. In a draft gear, a case, friction members within the case, a", plurality of pairs of friction shoes, each of said pairs being in frictional enl gagement with a corresponding one of said members, a wedge engaging said shoes, a spring interposed between an end wall of the case and said shoes for compression by relative movement between said shoes and said case, said shoes and said friction members overlapping said spring longigagement with a corresponding one of said members, a wedge external to the case and engaging said shoes, said wedge being so constructed and arranged as to apply wedging pressure simultaneously in opposite directions to the respective shoes of each pair, a spring interposed between an end wall of the case and said shoes for compression by relative movement between said shoes and said case, said shoes and said friction members overlapping said spring longitudinally, and the shoes of each pair engaging opposite sides of the corresponding friction member, said wedge and said case each having a slot for the reception of a draft key. 7

13. In a draft gear, a case, friction members within the case, afplurality of pairs of friction shoes, each of said pairs being in frictional engagement with a corresponding one of said members on opposite sides thereof, a wedge engaging said shoes, a spring interposed between an end wall of the case and said shoes for compression by relative movement between said shoes and said case, saidshoes and said friction members overlapping said spring longitudinally, and the shoes of each pair engaging opposite sides of the corresponding friction member, said wedge and said case each having a slotfor the reception of a draft key.

14. In a draft gear, a case, friction members within the case, a plurality of pairs of friction shoes, each pair in frictional engagement with a corresponding one of said friction members, spring means arranged to resist movement of said friction shoes, a wedge engaging said shoes, said wedge being outside said case and having pairs of interior wedging surfaces for cooperating with the respective pairs of shoes, the surfaces of each pair being arranged to apply pressure simultaneously in opposite directions to the corresponding pair of shoes, said wedge and case being each provided with means for receiving a draft key.

ERNEST H. SCHMIDT. 

